1. Field of the Invention
The invention is directed to a rod-type closure for locking preferably switch cabinet doors or the like doors or flaps, comprising a flat strip rod which is arranged so as to be guided parallel to the door edge, preferably in the bevel space, and has at least one locking part arranged thereon, further comprising a closure element arranged on the door frame for receiving the locking part such that it locks, and with an actuating device for the longitudinal displacement of the flat strip rod between an opening position and a locking position.
2. Description of the Prior Art
A rod-type closure of this kind is already known from EP 0 261 268.
In sheet-metal cabinets with leaf-type cabinet doors which are provided with an angled edge and accordingly form a bevel space, the requirements for the closing action of the rod-type closure are especially high because such doors have only limited stability. Cabinet doors of this type can warp and deform under certain conditions. Moreover, these doors are exposed to particularly high stresses in certain applications. For example, when used as doors of electric switch cabinets containing high-voltage switches, arcing can occasionally occur inside the cabinet, resulting in explosive release of arc gases which leads to high pressure loading of the doors.
For this reason it is important that rod-type closures provided for such sheet-metal cabinets are constructed in such a way that they connect the door securely with the body of the cabinet so that the door can also receive the loads mentioned above. In this regard, the shape and bearing of the locking rods with their locking parts deserve particular attention.
According to EP 0 261 268, the flat strip rod has pins making up the locking part, these pins being round in cross section and attached to the flat strip material, for example, by riveting. During the closing process, these pins move into a bracket with a U-shaped section or profile.
In a rod-type closure known from DE 42 10 586 A1 which is similar to the type mentioned above, a 90-degree turn serves as a locking part of the flat strip rod, while a hook-shaped structural component part is used as closure element.
A disadvantage in the first reference cited above consists in its relatively complicated construction which should be simplified while retaining the advantages already achieved. The other reference has the disadvantage that the starting region formed by the turn in the flat strip rod in the locking area causes problems in that the rear engagement formed in this way leads to high friction and accordingly also to high wear and impedes movement during the moving in process. Another disadvantage consists in that the turn extends toward both sides and accordingly results in a relatively broad construction, although only one of these two sides is usable, so that there is an unnecessary waste of space. Further, the rotational loading of the rod is quite extensive, which likewise increases the friction in the rod guides and further increases the forces needed for actuating.